Many devices have been developed to provide corrugations or undulations to a web of material. For example, U.S. Pat. No. 2,016,290 shows a pair of intermeshing toothed gears or belts used to form web corrugations in between intermeshing teeth. The web is fed in and bent around the teeth to form wave pattern.
U.S. Pat. No. 2,350,996 discloses an apparatus having a pair of endless chains which carry tooth-like members which interengage along a straight path. The interengaging tooth-like members compress a web between the teeth on one chain and the teeth on the other thus providing a wavy profile to the compressed web.
U.S. Pat. No. 2,303,381 shows a sewing apparatus which is particularly directed to the sewing of neckties. This apparatus uses a pair of intermeshing gears to corrugate a web by feeding the web through the intermeshing gears to provide the wavy pattern to the web. The web is then fed onto a needle and pulled down by a pair of pincher rollers which bunch up the web on the needle on the downstream side of the pincher rollers.
U.S. Pat. No. 2,695,652 shows a method of treating and corrugating a unit of strip material. The material is fed into a bath and then drawn along two endless chains having knobs thereon which intermesh. The knobs provide the web with an open wavy pattern which is maintained after the web leaves the nip area between the two chains and their intermeshing knobs.
U.S. Pat. No. 2,374,033 is a reference directed to a mechanism for making neckties also. This mechanism uses a pair of crimping bands which have intermeshing teeth which fold the corrugations of a web fed therebetween in order to crepe the material for a necktie lining.
U.S. Pat. No. 2,816,520 also shows a necktie sewing machine. This device uses a pair of parallel chains having angle crimpers and rod crimpers which mate to crepe the lining of a necktie. The lining is then fed on a needle through openings formed in the angle crimpers.
U.S. Pat. Nos. 2,871,807; 3,034,942; 3,516,116; 3,804,688; 3,922,129; 4,046,612; and 4,140,564 all disclose similar methods of corrugating or forming a waving pattern in a web by feeding the web through the nip of intermeshing teeth-like members either on gears or on a pair of parallel spaced belts.
U.S. Pat. No. 2,992,673 shows a apparatus for making cellular structures wherein pins are mounted on an endless conveyer in order to weave a pattern on a web fed therealong. The pins move into a position either above or below the web and then are moved vertically to the direction of the web to cause the web to be bent therebetween to form the internal portion of the cell structures.
U.S. Pat. No. 3,150,576 discloses feeding a web onto a moving irregular surface such that the web is blown against the surface to conform thereto. The web is then removed from the surface and maintains its structure in conformance with the moving surface on which it was laid.
U.S. Pat. No. 4,132,581 discloses an apparatus and method for forming plastic board. The apparatus includes the use of a corrugation forming station which forms a corrugated pattern to an internal piece of the plastic board. A toothed belt is synchronized with this corrugation forming station such that the teeth are received within the corrugations formed thereby.
In each of these devices, the corrugations are formed by a support which moves at a constant speed. Thus, the material must be fed onto the support and immediately takes its final shape usually by clamping the material on opposite sides by devices having the final corrugation pattern. These types of machines do not operate well with tight corrugations of webs, especially when tight corrugation in thicker resilient webs are desired. The devices are not available to make corrugations which have adjacent legs close or touching. Such high corrugation ratios have been left to apparatus which feed a web into a confined area where it is slowed, confined and caused to bunch up. The confines of the zone, however, limit the size of the corrugations.